1. Field of the Invention
The invention relates to a screen shade for use on a digital camera with an LCD display (screen). The invention also relates to a digital camera with a fitting for such a screen shade and for the fitting.
2. Description of Related Art
The LCD screen on a digital camera serves both in directing the camera when taking a photograph, i.e., as a classic viewfinder, and also for looking at and assessing the pictures already taken and stored in the camera. This double function has led to the LCD screens being made ever larger as the digital camera has developed, and at the time of this application, they are rarely less than 20 cm2.
The LCD screen on a digital camera is typically located on the rear of the camera""s body or casing so that the screen is more or less flat with the rear of the camera. It is easily accessible at all times in this location. However, this position is also problematic if the digital camera is to be used in the presence of a bright light source, e.g., outside in bright sunlight, or in the presence of spot lights in closed rooms. Even an extensive non-reflective LCD screen reflects so much light under these circumstances that the LCD image on a non-illuminated screen can barely be seen. At least this can be corrected for pictures already taken and stored in the camera by shading the screen by hand so that the image can be seen, but when using the screen as a classic viewfinder, this method of shading does not help since the camera can no longer be held in two hands ready to take the photograph.
Digital cameras, therefore, are typically fitted with an ordinary viewfinder as well as with the LCD screen. However, this not only has the disadvantage of making the construction costs for the camera more expensive, but also especially has the disadvantage of making the camera almost unusable in close photographyxe2x80x94for which digital cameras are especially powerfulxe2x80x94due to the parallaxes between the lens and the viewfinder. This is also the case for the use of lenses which extend or shorten the focal length which at least partly cover the viewfinder.
The same problems arise for digital cameras which have a reflex mechanism similar to that of a reflex camera, instead of a separate optical viewfinder. The photographer can only assess the panorama in front of the camera lens with this type of construction, even if only through the lens rather than through the optical viewfinder. However, due to the reflex mirror, the photographer is not in a position to assess the image stored in the camera before ultimately saving the image. Electronic viewfinders have the disadvantage that they only produce a very rough image which is of little use for arranging a picture. For professional photographers, therefore, neither the additional optical viewfinder nor the reflex mirror principle is a satisfactory solution for the problem of the LCD image which is barely discernable in the presence of strong light.
A further problem of digital cameras only fitted with an LCD screen is also one of their most important positive and attractive features, namely the exceptionally light and small construction, even for extremely powerful digital cameras. For professional pictures, however, these small digital cameras, which are only fitted with an LCD screen, can no longer be held stable by both hands supporting the camera against the head of the photographer in the form of a stable triangle.
Based on this state of technology, the technical problem underlying the invention is to develop a digital camera, in particular a freeze frame digital camera or single picture digital camera, such that the LCD screen remains discernable in light and even in very bright surroundings, and so that the digital camera can still be held against the forehead of the photographer in the triangle support position, as with normal small cameras, without losing the advantages of miniaturization of the digital camera.
The invention solves this problem with a screen shade for using a digital camera which has a removable fitting with adhesive for attaching a screen shade as described herein below.
The substance of the invention is based on creating a telescopic screen shade which is easy to fit and remove. The screen shade not only guarantees easy fitting by simply pressing it onto the rear of the camera, whether using Velcro strips or a notch connection, a bayonet fitting or other equivalent fitting, but it also allows the screen shade to be removed from the camera quickly and smoothly. The small, moveable and light construction of a digital camera, which are priorities when using the camera, even with powerful cameras, remains when using a screen shade according to the invention since this can be simply dismantled and stored in a case.
The telescopic feature of the screen shade, however, allows the camera to be relatively compact with the screen shade transport-ready, i.e., attached but not extended. Through its effective shading, even when light is coming relatively steeply from above, the screen shade allows the use of the screen shade telescoped outward as a type of optical viewfinder, while a larger view of the LCD screen with both eyes is possible by withdrawing the telescope or moving the lens. Such a view also allows an immediate assessment of the images on the LCD screen even in relatively bright surroundings due to the reflex-free, and thus unrestricted, contrast-rich LCD image.
According to the design of the invention, the telescopic extension of the screen shade can be fixed, for example, by means of a friction connection, by form or pressure connection using an adhesive or by using lockable or nonlockable drive. Since, in practice, the required extension between the shortest and longest extension is rarely more than 100%, the screen shade should preferably be designed with just two telescopic sections.
Regardless of whether the screen shade is made of two or more telescopic sections, another important feature of the invention is a magnifying lens, preferably fitted inside the telescopic sections of the screen shade, in see-through direction, i.e., from the photographer towards the LCD screen, beneath the external edge of the innermost telescopic section so that this lens fills the entire internal cross section of the innermost telescopic section. This magnifying lens also has an advantageous design as an anti-reflective non-reflective plane-convex condenser lens. As a result of this design of an anti-reflective magnifying lens, preferably, located 5-20 mm below the outermost edge of the telescopic screen shade, any external light can be prevented from accidentally entering the screen shade so that a reflection-free view of the LCD screen is guaranteed in practically all light conditions. The focal power of this lens is to be measured such that an optical magnification of the LCD screen is achieved when the magnifying lens is fully withdrawn, which allows an immediate assessment of focus, resolution and contrast without the resolution of the notch of the LCD being affected as a result of the magnification. According to this feature, for an optimum distance of the lens from the LCD screen, preferably of 60-95 mm, where external light can no longer penetrate, the lens""s focal power should be in the region of 5.5 to 7.5 diopters (dpt), in particular, a focal power of +6.5 diopters.
For use as a viewfinder, the screen shade is focused and fixed by extending the magnifying lens so that the photographer can see the image on the LCD screen clearly with one eye while holding the end of the screen shade against the head. While the focus can be adjusted by moving the screen shade, and thus the magnifying lens, in and out when using only one eye, for optimal use of the magnifying function of the screen shade when using both eyes, the lens should be pushed in and the focus of the screen can be adjusted by changing the distance of the magnifying lens in the screen shade from the eyes.
A substantial feature of the practicability of the screen shade with the features of the invention is its fast and smooth attaching and removing while also having an absolutely reliably firm fitting on the camera against accidental removal. Preferably, this is guaranteed, by a feature of the invention, by pressing the screen shade on the rear of the camera using a notch connection produced by snaps which fix the screen shade to the camera using a shaped rear section. According to the design of the invention, this is realized through two bars of notches with holes which are arranged in parallel to two opposing sides of the LCD screen and which can be released or firmly attached to the camera""s casing. One of these two bars of notches is designed as a rigid bar while the opposite bar is at least partially resilient.
The screen shade has complementing rigid snaps which are placed into the opposing openings in the bars when using the screen shade, and which also enter the opposing openings on the other side by briefly bending the resilient bar when pressing the screen shade. In this position, the screen shade and the digital camera cannot be separated and are rigidly and reliably connected by the connection. In order to remove the screen shade, on the other hand, a simple pressing of the resilient bar is required while pulling the screen shade from the rigid connectors. The resilient release of the screen shade connector can be made simpler by a corresponding element on the resilient bar, for example, a tongue or a simple rounding of the upper edge of the resilient bar. This rounding can also serve as a guide for the connector.
Moving the magnifying lens from the viewfinder function to the image viewing function can be by connecting it to the telescopic section of the screen shade and moving everything in and out. In this case, it is beneficial if an additional reflection protection tube is fitted independently of the telescopic section holding the lens.
However, a design is preferred where the magnifying lens is fitted on a lens holder independently of the section of the screen shade holding it, such that the magnifying lens can be moved with the lens holder into the image viewing position while the section of the screen shade farthest from the camera casing remains in the function of a reflection protection tube. A separate reflection protection tube is thus fully superfluous.